1. Field of the Invention
The present invention relates to a projection lens for enlarging and projecting images formed on a conjugation surface on a reduction side onto a conjugation surface on a magnification side and a projection-type display apparatus using the lens.
2. Description of the Related Art
A transmissive/reflective light valve using liquid crystal and the like, a small projection lens using DMD's that modulate light by deflecting arranged micro mirrors, as well as a projection-type display apparatus (also called projectors) using the lens are conventionally known.
In recent years, the market for such projectors has expanded along with the popularization of personal computers, light valves have been miniaturized, and light sources have been made more highly efficient. Such background requires commercialization of readily portable compact projectors.
As a projection lens constituting such readily portable projectors, a projection lens which has a reduced number of constituent lenses are particularly known (refer to Japanese Unexamined Patent Publication No. 2004-361651, Japanese Unexamined Patent Publication No. 2010-097078, and Japanese Unexamined Patent Publication No. 2010-175832).